I was hiking in the wilderness near Denali National Park, when I came across a scree slope. Being an adventurous person, I started to climb up. However, somewhere along I came
across this. I have a few questions:

Geodes differ from vugs in that the former were formed as early, rounded, structures within the surrounding rock and are often removed intact, whereas vugs are irregularly shaped pockets, voids or cavities within a formation, often along a vein or in breccia. Geodes also differ from "nodules" in that a nodule is a mass of mineral matter that has accreted around the nodule nucleus. Both structures had the minerals contained within, deposited from groundwater or hydrothermal processes. Geodes commonly have a chalcedony (cryptocrystalline quartz) shell lined internally by various minerals, often as crystals, particularly calcite, pyrite, kaolinite, sphalerite, millerite, barite, celestite, dolomite, limonite, smithsonite, opal, chalcedony and macrocrystalline quartz, which is by far the most common and abundant mineral found in geodes. Geodes are found mostly in basaltic lavas and limestones. The Warsaw Formation in the Keokuk region near the area where Missouri, Iowa, and Illinois join contains abundant geodes. Got this from Wikipedia, seems accurate. Your piece may be a vug, or breccia filling, a geode is a fairly definite object. As has been said about a certain form of literature, I can't tell you what it is, but I know it when I see it. It seems to be calcite, could be a speleothem or flow stone, just a guess.

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